Dephosphorylation of Centrins by Protein Phosphatase 2C α and ß.

In the present study, we identified protein phosphatases dephosphorylating centrins previously phosphorylated by protein kinase CK2. The following phosphatases known to be present in the retina were tested: PP1, PP2A, PP2B, PP2C, PP5, and alkaline phosphatase. PP2C α and ß were capable of dephosphorylating P-Thr(138)-centrin1 most efficiently. PP2Cδ was inactive and the other retinal phosphatases also had much less or no effect. Similar results were observed for centrins 2 and 4. Centrin3 was not a substrate for CK2. The results suggest PP2C α and ß to play a significant role in regulating the phosphorylation status of centrins in vivo.